A thing called human
by MoonlightTaylor
Summary: In which Castiel becomes human and learns to love humanity just a little bit more.


**_A Thing Called Human_**

Summary: In which Castiel becomes human and learns to love humanity just a little bit more.

 _"Are all humans like this? [...] So much bigger on the inside." - the TARDIS/Idris, The Doctor's Wife, Doctor Who_

Castiel is part stardust, part imagination, part iridescent light. He grew up playing with galaxies. All those nebulas and stars; Cas liked to pick them up one by one, run his finger over planets, roll comets like marbles through the vast infinity.

When he was older, his brothers would take him into those galaxies, the ones that had slipped so casually through his fingers. They would shrink to the size of molecules, shudder along with the rhythm of the stars and Castiel learned that each of those tiny little galaxies was immense and immeasurable. Each of them was a world in and of itself.

And since then he has fought cosmic battles, weathered the worst of Jupiter's storms and stood, watching as stars breathed their last breath. None of this was a strange and spectacularly complicated as being human.

/

There is a certain thrumming to the universe, a certain swirl. The only human thing Castiel could compare it to is an ocean, full with shimmering galaxies. He knows the taste of an atom, hums the music of the stars. He knows what it is to feel the colour purple, has been intoxicated by the rich smell of anti-matter and has basked in the warmth of dirt when it gritted through him as comets and planets scattering into everything.

Before he was human, he never had a name for these things. They were obvious, part of the crawl of time. How was he to know that humans didn't feel their planet turning, that they couldn't hear the earth's plates grinding ever together, or smell the sunlight drifting through the air?

He had known humans were dull of course, that they were blind and deaf in comparison to an angel. But now, knowing how little they experience the universe, Castiel marvels all the more at how much they feel. Dad gave them free will, and they took everything they didn't know and didn't hear and didn't feel and turned it in on themselves.

All those millennia looking down at these undiscerning creatures on this useless little planet, and Castiel had never seen what God must have seen all along. If these creatures couldn't feel the universe around them, then they would make one in their soul.

They looked at the stars, but couldn't hear the music. So they filled that hole and called it happiness and they made music of their own. And if they couldn't taste the wind then they sought for something just as exhilarating, and found it in another's tongue and they called it love. When the moon tugged at the ocean and they couldn't feel it, they cried and called it sorrow. They tried, but they couldn't touch the bottom of the ocean so they made up stories and they called it fear.

All these emotions, Castiel has known them from the beginning. They just have different names to angels.

Nostalgia is the scrape of a planet against the dark. Wonder is the whisper of a water drop and the breath of a star. Disgust is the churning smell of single grain of sand. Hope is the millions of colours that don't have a name because humans can't see them. Grief is the slip of blood in a lion's veins and the clenching roots of a cactus.

These things echo in Castiel, have echoed through him in every form; from small child skipping through the milky way, to the hardened warrior with the a sword clenched like lion's blood between his fingers. And now he can no longer see these things, but he still understands them. He feels them, not around him, but inside him. A great big everything just waiting to explode.

/

There are other emotions humans don't have a name for. Things angels, despite their long life spans, are too impatient for. While Castiel had understood the concept of beauty, had seen it in the stars and in the reflection of light off the trees on earth, he had never understood it the way he does now.

There is no name for the emotion of finding something beautiful, the way it both breaks and mends the heart. Seeing the sun sinking slowly behind bare, spindly trees bring unexpected tears to Cas' eyes. These naked trees, dead-looking as they stand out against the warm pink of the sky, they taste somehow bittersweet.

It is nothing he hasn't seen before. In fact, if he were still an angel he would have been able to see every speck, every ridge, every glitter of light. Maybe some things are better when the senses are dulled. Perhaps this is why humans intoxicate themselves, to see less but feel more.

And now with beauty, Castiel understands war. He had never understood why humans would could destroy each other with one hand, and use the other to hold each other close. Now he he has felt the beauty of tragedy, like the joy in a burning star. It haunts him, these two things that should never mix.

If you have a universe within you, then there are times when all these emotions are too big for that small little soul. They circle and grow and crash together; ice cubes in a cocktail shaker. Until it grows too big and bursts.

This explosion is familiar to Cas. Even angels know violence.

/

Then there were things that only humans feel.

Mortality, for one thing, is very much part of the human universe, but there was no angelic feeling to match. There is no colour to describe the knowledge that you are only a small facet in a much bigger picture, that there are millions upon millions of things you will never see or feel or experience. The knowledge that there has been so much before you, and that there will be so much after you are gone. That your life is a mere blip in comparison to everything else. Every human is aware of this, but to an angel it is brand new.

And so humans cling to their life with a fervor that is frankly enviable to an angel. There is a certain taste to that, metallic blood and scraping bone, that an angel will never feel. Angels have an existence, humans have a life; a lust for seeing and doing. Even if their life is painful and tragic and useless, a human will still dig their heels into the dust of the universe against the pull of death.

This is put in perspective, then, by the strange fondness humans seem to have for sacrifice. It seems there is only one thing that overrides the innate need to survive, and this is love. Not love in an angelic sense - wide and generic - but a love so large and and encompassing that an eternity of nothing is more appealing than a life lived without someone.

/

Stubborn, stupid and just a little bit broken. And so very much bigger on the inside.

Castiel had thought the Winchesters were a peculiar set of humans, different from all the rest that crawled like ants over God's beloved Earth. They are not anything more than human. In fact, they are the most human humans he knows. So full of emotions, so willing to pretend they are empty inside.

Peanut butter and jelly tastes like too many things on this tongue. It has none of the roundness, gives none of the contentment it used to. Things have gone back to normal, but something inside him has changed. Castiel had always felt a fullness inside him, something large and curious swirling so much like the galaxies around him. He never had a name for it. Now he does.

It is a longing for the unknown. It is a thing called human.

 _Disclaimer: I do not own Supernatural or Doctor Who, though I borrowed a little from both for this piece of incoherent prose._


End file.
